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1.
Surg Oncol ; 38: 101597, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34051659

RESUMO

In a previous pilot study, we showed that polyunsaturated n-3 fatty acids of breast adipose tissues were associated with breast cancer multifocality. In the present study, we investigated biochemical, clinical and histological factors associated with breast cancer focality in a large cohort of women with positive hormone-receptors tumors. One hundred sixty-one consecutive women presenting with positive hormone-receptors breast cancer underwent breast-imaging procedures including a Magnetic Resonance Imaging prior to treatment. Breast adipose tissue specimens were collected during surgery of tumors. A biochemical profile of breast adipose tissue fatty acids was established by gas chromatography. Clinicopathologic characteristics were correlated with multifocality. We assessed whether these factors were predictive of breast cancer focality. We found that tumor size (OR = 1.06 95%CI [1.02-1.09], p < 0.001) and decreased levels in breast adipose tissue of long-chain polyunsaturated n-3 fatty acids (OR = 0.11 95%CI [0.01-0.98], p = 0.03), were independent predictive factors of multifocality. Low levels of long chain polyunsaturated n-3 fatty acids in breast adipose tissue appear to contribute to breast cancer multifocality. The present results reinforce the link between dietary habits and breast cancer clinical presentation.


Assuntos
Tecido Adiposo/patologia , Neoplasias da Mama/patologia , Ácidos Graxos Ômega-3/metabolismo , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Tecido Adiposo/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/metabolismo , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Invasividade Neoplásica , Prognóstico
2.
Eur J Med Chem ; 218: 113258, 2021 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-33813152

RESUMO

Herein, we report the design, synthesis and evaluation of novel bioinspired imidazo[1,2-a:4,5c']dipyridines. The structural optimization identified four anti-proliferative compounds. Compounds 11, 18, 19 and 20 exhibited excellent anticancer activities in vitro with IC50 of 0.4-5 µM against three human cancer cell lines (MDA-MB-468, MDA-MB-435s and MDA-MB-231). These four compounds induced apoptosis in MDA-MB-231 cells in a dose-dependent manner, targeting different apoptotic proteins expression: 11 increased the expression of pro-apoptotic Bax protein while 18-20 reduced the level of anti-apoptotic Bcl-2 protein. Compounds 18 and 19 also reduced MDA-MB-231 cells proliferation as measured by Ki-67 staining. Furthermore, compounds were also tested for the ability to inhibit cell migration in the highly aggressive human MDA-MB-435s cell line. Six compounds of this series (8, 15, 18, 22, 23, 24) inhibited cell migration by 41-50% while four compounds (20, 25, 27, 30) inhibited the migration by 53-62% in wound-healing experiments. Interestingly, compound 20 presented both antiproliferative and anti-migration activities and might be a promising anti-metastatic agent for cancer treatment.


Assuntos
Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Relação Estrutura-Atividade , Células Tumorais Cultivadas
3.
Nutrients ; 12(12)2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33333962

RESUMO

In the present study, we investigated various biochemical, clinical, and histological factors associated with bone metastases in a large cohort of pre- and postmenopausal women with breast cancer. Two hundred and sixty-one consecutive women with breast cancer were included in this study. Breast adipose tissue specimens were collected during surgery. After having established the fatty acid profile of breast adipose tissue by gas chromatography, we determined whether there were differences associated with the occurrence of bone metastases in these patients. Regarding the clinical and histological criteria, a majority of the patients with bone metastases (around 70%) had tumors with a luminal phenotype and 59% of them showed axillary lymph node involvement. Moreover, we found a negative association between the levels of n-3 long-chain polyunsaturated fatty acids (LC-PUFA) in breast adipose tissue and the development of bone metastases in premenopausal women. No significant association was observed in postmenopausal women. In addition to a luminal phenotype and axillary lymph node involvement, low levels of n-3 LC-PUFA in breast adipose tissue may constitute a risk factor that contributes to breast cancer bone metastases formation in premenopausal women.


Assuntos
Tecido Adiposo/metabolismo , Neoplasias Ósseas/secundário , Neoplasias da Mama/patologia , Ácidos Graxos Ômega-3/metabolismo , Pré-Menopausa/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Mama/metabolismo , Mama/patologia , Neoplasias da Mama/metabolismo , Cromatografia Gasosa , Feminino , Humanos , Pessoa de Meia-Idade , Metástase Neoplásica , Fenótipo , Pós-Menopausa/metabolismo , Estudos Retrospectivos , Fatores de Risco
4.
Cancers (Basel) ; 12(9)2020 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-32825056

RESUMO

The P2X7 receptor is an ATP-gated cation channel with a still ambiguous role in cancer progression, proposed to be either pro- or anti-cancerous, depending on the cancer or cell type in the tumour. Its role in mammary cancer progression is not yet defined. Here, we show that P2X7 receptor is functional in highly aggressive mammary cancer cells, and induces a change in cell morphology with fast F-actin reorganization and formation of filopodia, and promotes cancer cell invasiveness through both 2- and 3-dimensional extracellular matrices in vitro. Furthermore, P2X7 receptor sustains Cdc42 activity and the acquisition of a mesenchymal phenotype. In an immunocompetent mouse mammary cancer model, we reveal that the expression of P2X7 receptor in cancer cells, but not in the host mice, promotes tumour growth and metastasis development, which were reduced by treatment with specific P2X7 antagonists. Our results demonstrate that P2X7 receptor drives mammary tumour progression and represents a pertinent target for mammary cancer treatment.

5.
Lipids ; 55(4): 403-412, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32424826

RESUMO

Lipids such as cholesterol, triacylglycerols, and fatty acids play important roles in the regulation of cellular metabolism and cellular signaling pathways and, as a consequence, in the development of various diseases. It is therefore important to understand how their metabolism is regulated to better define the components involved in the development of various human diseases. In the present work, we describe the development and validation of a high-performance thin layer chromatography (HPTLC) method allowing the separation and quantification of free cholesterol, cholesteryl esters, nonesterified fatty acids, and triacylglycerols. This method will be of interest as the quantification of these lipids in one single assay is difficult to perform.


Assuntos
Mama/química , Lipídeos/análise , Extratos de Tecidos/química , Mama/patologia , Linhagem Celular Tumoral , Colesterol/análise , Ésteres do Colesterol/análise , Cromatografia em Camada Fina , Ácidos Graxos não Esterificados/análise , Humanos , Células MCF-7 , Triglicerídeos/análise
6.
Sci Rep ; 9(1): 18652, 2019 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-31819138

RESUMO

Loss of epithelial polarity and gain in invasiveness by carcinoma cells are critical events in the aggressive progression of cancers and depend on phenotypic transition programs such as the epithelial-to-mesenchymal transition (EMT). Many studies have reported the aberrant expression of voltage-gated sodium channels (NaV) in carcinomas and specifically the NaV1.5 isoform, encoded by the SCN5A gene, in breast cancer. NaV1.5 activity, through an entry of sodium ions, in breast cancer cells is associated with increased invasiveness, but its participation to the EMT has to be clarified. In this study, we show that reducing the expression of NaV1.5 in highly aggressive human MDA-MB-231 breast cancer cells reverted the mesenchymal phenotype, reduced cancer cell invasiveness and the expression of the EMT-promoting transcription factor SNAI1. The heterologous expression of NaV1.5 in weakly invasive MCF-7 breast cancer cells induced their expression of both SNAI1 and ZEB1 and increased their invasive capacities. In MCF-7 cells the stimulation with the EMT-activator signal TGF-ß1 increased the expression of SCN5A. Moreover, the reduction of the salt-inducible kinase 1 (SIK1) expression promoted NaV1.5-dependent invasiveness and expression of EMT-associated transcription factor SNAI1. Altogether, these results indicated a prominent role of SIK1 in regulating NaV1.5-dependent EMT and invasiveness.


Assuntos
Neoplasias da Mama/genética , Canal de Sódio Disparado por Voltagem NAV1.5/genética , Proteínas Serina-Treonina Quinases/genética , Fator de Crescimento Transformador beta1/genética , Neoplasias da Mama/patologia , Movimento Celular/genética , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Células MCF-7 , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Fatores de Transcrição da Família Snail/genética , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genética
7.
Breast ; 45: 113-117, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30959386

RESUMO

OBJECTIVE: Since it is thought that breast adipose tissue could influence breast cancer clinical presentation, we wanted to characterize specifically the relationship between breast adipose tissue fatty acid profile and Inflammatory Breast cancer (IBC). METHODS: Two hundred thirty-four women presenting with breast cancer were managed in our centre between January 2009 and December 2011. Breast adipose tissue specimens were collected during breast surgery. We established the biochemical profile of adipose tissue fatty acids (FA) by gas chromatography and assessed whether there were differences in function of the presence of breast inflammation or not. RESULTS: We found that IBC was associated with decreased levels in breast adipose tissue of eicosapentaenoic acid (EPA), one of the two main polyunsaturated n-3 fatty acids (n-3 PUFA) of marine origin, but also with decreased levels of Gamma Linolenic acid (GLA). Inversely, an increase in palmitic acid levels was associated with IBC. CONCLUSION: These differences in lipid content may contribute to the occurrence of breast cancer inflammation.


Assuntos
Tecido Adiposo/metabolismo , Neoplasias da Mama/metabolismo , Mama/metabolismo , Ácido Eicosapentaenoico/metabolismo , Neoplasias Inflamatórias Mamárias/metabolismo , Ácido gama-Linolênico/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Cromatografia Gasosa , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos
8.
Mar Drugs ; 16(4)2018 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-29570630

RESUMO

Natural O-alkyl-glycerolipids, also known as alkyl-ether-lipids (AEL), feature a long fatty alkyl chain linked to the glycerol unit by an ether bond. AEL are ubiquitously found in different tissues but, are abundant in shark liver oil, breast milk, red blood cells, blood plasma, and bone marrow. Only a few AEL are commercially available, while many others with saturated or mono-unsaturated alkyl chains of variable length are not available. These compounds are, however, necessary as standards for analytical methods. Here, we investigated different reported procedures and we adapted some of them to prepare a series of 1-O-alkyl-glycerols featuring mainly saturated alkyl chains of various lengths (14:0, 16:0, 17:0, 19:0, 20:0, 22:0) and two monounsaturated chains (16:1, 18:1). All of these standards were fully characterized by NMR and GC-MS. Finally, we used these standards to identify the AEL subtypes in shark and chimera liver oils. The distribution of the identified AEL were: 14:0 (20-24%), 16:0 (42-54%) and 18:1 (6-16%) and, to a lesser extent, (0.2-2%) for each of the following: 16:1, 17:0, 18:0, and 20:0. These standards open the possibilities to identify AEL subtypes in tumours and compare their composition to those of non-tumour tissues.


Assuntos
Cromatografia Gasosa/normas , Óleos de Peixe/química , Glicerídeos/síntese química , Fígado/química , Tubarões , Animais
10.
Biochim Biophys Acta Mol Basis Dis ; 1863(6): 1292-1299, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28392417

RESUMO

BACKGROUND: Mitochondrial Trifunctional Protein deficiency (TFPD) is a severe genetic disease characterized by altered energy metabolism and accumulation of long-chain (LC) acylcarnitines in blood and tissues. This accumulation could impair the mitochondrial oxidative phosphorylation (OxPhos), contributing to the non-optimal outcome despite conventional diet therapy with medium-chain triglycerides (MCT). METHOD: Acylcarnitine and OxPhos parameters were measured in TFPD-fibroblasts obtained from 8 children and cultured in medium mimicking fasting (LCFA) or conventional treatment (MCT), with or without Etomoxir (ETX) an inhibitor of carnitine palmitoyltransferase 1 (CPT1) activity, and were compared to results obtained with fibroblasts from 5 healthy-control children. The effects of various acylcarnitines were also tested on control fibroblasts. RESULTS: In the LCFA-condition, TFPD-fibroblasts demonstrated a large accumulation of LC-acylcarnitines associated with decreased O2-consumption (63±3% of control, P<0.001) and ATP production (67±5%, P<0.001) without modification of coupling efficiency. A dose-dependent decrease in O2-consumption was reproduced in control fibroblasts by addition of increasing dose of LC-acylcarnitines, while it was almost preserved with MC-acylcarnitines. The MCT-condition reduced LC-acylcarnitine accumulation and partially improved O2-consumption (80±3%, P<0.01) in TFPD-fibroblasts. The addition of ETX in both LCFA- and MCT-conditions normalized acylcarnitine profiles and restored O2-consumption and ATP production at the same levels than control. CONCLUSION: Accumulation of LC-acylcarnitines plays a major role in the pathophysiology of TFPD, reducing OxPhos capacities. These deleterious effects could be partially prevented by MCT-therapy and totally corrected by ETX. Inhibition of CPT1 may be view as a new therapeutic target for patients with a severe form of TFPD.


Assuntos
Cardiomiopatias/metabolismo , Carnitina O-Palmitoiltransferase/antagonistas & inibidores , Compostos de Epóxi/farmacologia , Fibroblastos/metabolismo , Erros Inatos do Metabolismo Lipídico/metabolismo , Mitocôndrias/metabolismo , Miopatias Mitocondriais/metabolismo , Proteína Mitocondrial Trifuncional/deficiência , Doenças do Sistema Nervoso/metabolismo , Fosforilação Oxidativa/efeitos dos fármacos , Rabdomiólise/metabolismo , Cardiomiopatias/patologia , Carnitina O-Palmitoiltransferase/metabolismo , Feminino , Fibroblastos/patologia , Humanos , Lactente , Recém-Nascido , Erros Inatos do Metabolismo Lipídico/patologia , Masculino , Mitocôndrias/patologia , Miopatias Mitocondriais/patologia , Proteína Mitocondrial Trifuncional/efeitos dos fármacos , Proteína Mitocondrial Trifuncional/metabolismo , Doenças do Sistema Nervoso/patologia , Rabdomiólise/patologia
11.
Semin Cancer Biol ; 43: 90-110, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28323020

RESUMO

While tumours arise from acquired mutations in oncogenes or tumour-suppressor genes, it is clearly established that cancers are metabolic diseases characterized by metabolic alterations in tumour cells, and also non-tumour cells of the host organism resulting in tumour cachexia and patient weakness. In this review, we aimed at delineating details by which metabolic alterations in cancer cells, characterized by mitochondrial bioenergetics deregulations and the preference for aerobic glycolysis, are critical parameters controlling the aggressive progression of tumours. In particular, metabolic alteration in cancer cells are coupled to the modulation of intracellular and extracellular pH, epithelial-to-mesenchymal transition and associated increased invasiveness, autophagy, and the development of anticancer treatment resistance. Finally, based on mechanistic, pre-clinical and clinical studies, we proposed the adjuvant supplementation of dietary n-3 polyunsaturated fatty acids for a complementary holistic treatment of the cancer disease.


Assuntos
Antineoplásicos/uso terapêutico , Gorduras na Dieta/administração & dosagem , Concentração de Íons de Hidrogênio , Neoplasias/tratamento farmacológico , Progressão da Doença , Transição Epitelial-Mesenquimal , Humanos , Mitocôndrias/metabolismo , Neoplasias/metabolismo , Neoplasias/patologia
12.
Biochim Biophys Acta Gen Subj ; 1861(5 Pt A): 1075-1084, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28214549

RESUMO

BACKGROUND: We hypothesized that, among the mechanisms of drug-resistance acquired by doxorubicin (DOX)-resistant breast cancer cells to maintain cell survival, ATP-dependent drug efflux pumps could be expressed in their mitochondrial membranes and this might limit the accumulation of DOX in this subcellular compartment in relation to mitochondrial ATP production. METHODS/RESULTS: Mitochondrial DOX accumulation: the presence and the activity of mitochondrial efflux pumps and their relationship with mitochondrial ATP synthesis were analyzed in DOX-resistant (MCF-7doxR) and -sensitive (MCF-7S) breast cancer cells. Mitochondrial accumulation of DOX (autofluorescence) was decreased when ATP was produced, but only in MCF-7doxR. In these DOX-resistant cells, breast cancer resistance protein (BCRP) and multidrug resistance-associated protein (MRP1) were expressed and localized in mitochondria (confocal microscopy and confocal spectral imaging studies). In addition, mitochondrial accumulation of DOX was increased by BCRP and MRP1 inhibitors and, to a lower extent, by the mitochondrial ATP synthase inhibitor, oligomycin, in MCF-7doxR. CONCLUSIONS: Both BCRP and MRP1 were localized in mitochondria and participated to the reduction of mitochondrial accumulation of DOX in MCF-7doxR. This process was partly dependent of mitochondrial ATP synthesis. GENERAL SIGNIFICANCE: The present study provides novel insights in the involvement of mitochondria in the underlying mechanisms of DOX-resistance in breast cancer cells.


Assuntos
Trifosfato de Adenosina/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos/fisiologia , Mitocôndrias/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Resistência a Múltiplos Medicamentos/fisiologia , Feminino , Humanos , Células MCF-7 , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Proteínas de Neoplasias/metabolismo
13.
Nat Commun ; 7: 13648, 2016 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-27917859

RESUMO

The development of metastases largely relies on the capacity of cancer cells to invade extracellular matrices (ECM) using two invasion modes termed 'mesenchymal' and 'amoeboid', with possible transitions between these modes. Here we show that the SCN4B gene, encoding for the ß4 protein, initially characterized as an auxiliary subunit of voltage-gated sodium channels (NaV) in excitable tissues, is expressed in normal epithelial cells and that reduced ß4 protein levels in breast cancer biopsies correlate with high-grade primary and metastatic tumours. In cancer cells, reducing ß4 expression increases RhoA activity, potentiates cell migration and invasiveness, primary tumour growth and metastatic spreading, by promoting the acquisition of an amoeboid-mesenchymal hybrid phenotype. This hyperactivated migration is independent of NaV and is prevented by overexpression of the intracellular C-terminus of ß4. Conversely, SCN4B overexpression reduces cancer cell invasiveness and tumour progression, indicating that SCN4B/ß4 represents a metastasis-suppressor gene.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Movimento Celular , Genes Supressores de Tumor , Subunidade beta-4 do Canal de Sódio Disparado por Voltagem/genética , Animais , Neoplasias da Mama/ultraestrutura , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Progressão da Doença , Regulação para Baixo/genética , Células Epiteliais/metabolismo , Matriz Extracelular/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Ativação do Canal Iônico , Camundongos Nus , Invasividade Neoplásica , Metástase Neoplásica , Prognóstico , Subunidades Proteicas/metabolismo , Canais de Sódio/metabolismo , Subunidade beta-4 do Canal de Sódio Disparado por Voltagem/metabolismo , Peixe-Zebra , Proteína rhoA de Ligação ao GTP/metabolismo
14.
Front Pharmacol ; 7: 338, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27774064

RESUMO

Studies have demonstrated the significant role of cholesterol and lipoprotein metabolism in the progression of cancer. The SCARB1 gene encodes the scavenger receptor class B type I (SR-BI), which is an 82-kDa glycoprotein with two transmembrane domains separated by a large extracellular loop. SR-BI plays an important role in the regulation of cholesterol exchange between cells and high-density lipoproteins. Accordingly, hepatic SR-BI has been shown to play an essential role in the regulation of the reverse cholesterol transport pathway, which promotes the removal and excretion of excess body cholesterol. In the context of atherosclerosis, SR-BI has been implicated in the regulation of intracellular signaling, lipid accumulation, foam cell formation, and cellular apoptosis. Furthermore, since lipid metabolism is a relevant target for cancer treatment, recent studies have focused on examining the role of SR-BI in this pathology. While signaling pathways have initially been explored in non-tumoral cells, studies with cancer cells have now demonstrated SR-BI's function in tumor progression. In this review, we will discuss the role of SR-BI during tumor development and malignant progression. In addition, we will provide insights into the transcriptional and post-transcriptional regulation of the SCARB1 gene. Overall, studying the role of SR-BI in tumor development and progression should allow us to gain useful information for the development of new therapeutic strategies.

15.
Oncotarget ; 7(17): 23785-800, 2016 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-26993604

RESUMO

Expression of the antimicrobial peptide hCAP18/LL-37 is associated to malignancy in various cancer forms, stimulating cell migration and metastasis. We report that LL-37 induces migration of three cancer cell lines by activating the TRPV2 calcium-permeable channel and recruiting it to pseudopodia through activation of the PI3K/AKT pathway. Ca2+ entry through TRPV2 cooperated with a K+ efflux through the BKCa channel. In a panel of human breast tumors, the expression of TRPV2 and LL-37 was found to be positively correlated. The D-enantiomer of LL-37 showed identical effects as the L-peptide, suggesting that no binding to a specific receptor was involved. LL-37 attached to caveolae and pseudopodia membranes and decreased membrane fluidity, suggesting that a modification of the physical properties of the lipid membrane bilayer was the underlying mechanism of its effects.


Assuntos
Peptídeos Catiônicos Antimicrobianos/farmacologia , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/patologia , Cálcio/metabolismo , Movimento Celular/efeitos dos fármacos , Subunidades alfa do Canal de Potássio Ativado por Cálcio de Condutância Alta/metabolismo , Canais de Cátion TRPV/metabolismo , Peptídeos Catiônicos Antimicrobianos/química , Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Células Tumorais Cultivadas , Catelicidinas
16.
Biochim Biophys Acta ; 1861(4): 380-90, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26821209

RESUMO

Taxanes can induce drug resistance by increasing signaling pathways such as PI3K/Akt and ERK, which promote survival and cell growth in human cancer cells. We have previously shown that long chain n-3 polyunsaturated fatty acids, such as docosahexaenoic acid (DHA, 22:6n-3) decrease resistance of experimental mammary tumors to anticancer drugs. Our objective was to determine whether DHA could increase tumor sensitivity to docetaxel by down-regulating these survival pathways. In docetaxel-treated MDA-MB-231 cells, phosphorylated-ERK1/2 levels were increased by 60% in membrane and nuclear compartments, compared to untreated cells. Our data showed that ERK1/2 activation depended on PKC activation since: i) enzastaurin (a pan-PKC inhibitor) blocked docetaxel-induced ERK1/2 phosphorylation ii) docetaxel increased PKC activity by 30% and phosphatidic acid level by 1.6-fold iii) inhibition of PKCε and PKCδ by siRNA resulted in reduced phosphorylated ERK1/2 levels. In DHA-supplemented cells, docetaxel was unable to increase PKCε and δ levels in membrane and nuclear fractions, resulting in diminished ERK1/2 phosphorylation and increased docetaxel efficacy. Reduced membrane level of PKCε and PKCδ was associated with significant incorporation of DHA in all phospholipids, including phosphatidylcholine which is a major source of phosphatidic acid. Additionally, examination of the Akt pathway showed that DHA could repress docetaxel-induced Ser473Akt phosphorylation. In rat mammary tumors, dietary DHA supplementation during docetaxel chemotherapy repressed ERK and Akt survival pathways and in turn strongly improved taxane efficacy. The P-ERK level was negatively correlated with tumor regression. These findings are of potential clinical importance in treating chemotherapy-refractory cancer.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Ácidos Docosa-Hexaenoicos/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Proteína Quinase C-delta/metabolismo , Proteína Quinase C-épsilon/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Taxoides/farmacologia , Animais , Neoplasias da Mama/enzimologia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Docetaxel , Relação Dose-Resposta a Droga , Regulação para Baixo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Ativação Enzimática , Feminino , Humanos , Neoplasias Mamárias Experimentais/induzido quimicamente , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias Mamárias Experimentais/enzimologia , Neoplasias Mamárias Experimentais/patologia , Metilnitrosoureia , Fosforilação , Proteína Quinase C-delta/antagonistas & inibidores , Proteína Quinase C-delta/genética , Proteína Quinase C-épsilon/antagonistas & inibidores , Proteína Quinase C-épsilon/genética , Inibidores de Proteínas Quinases/farmacologia , Interferência de RNA , Ratos Sprague-Dawley , Fatores de Tempo , Transfecção , Carga Tumoral/efeitos dos fármacos
17.
PLoS One ; 11(1): e0147148, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26812254

RESUMO

OBJECTIVE: The microenvironment of breast epithelial tissue may contribute to the clinical expression of breast cancer. Breast epithelial tissue, whether healthy or tumoral, is directly in contact with fat cells, which in turn could influence tumor multifocality. In this pilot study we investigated whether the fatty acid composition of breast adipose tissue differed according to breast cancer focality. METHODS: Twenty-three consecutive women presenting with non-metastatic breast cancer underwent breast-imaging procedures including Magnetic Resonance Imaging prior to treatment. Breast adipose tissue specimens were collected during breast surgery. We established a biochemical profile of adipose tissue fatty acids by gas chromatography. We assessed whether there were differences according to breast cancer focality. RESULTS: We found that decreased levels in breast adipose tissue of docosahexaenoic and eicosapentaenoic acids, the two main polyunsaturated n-3 fatty acids of marine origin, were associated with multifocality. DISCUSSION: These differences in lipid content may contribute to mechanisms through which peritumoral adipose tissue fuels breast cancer multifocality.


Assuntos
Neoplasias da Mama/metabolismo , Ácidos Docosa-Hexaenoicos/metabolismo , Ácido Eicosapentaenoico/metabolismo , Tecido Adiposo Branco/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Dieta , Feminino , Humanos , Metabolismo dos Lipídeos , Glândulas Mamárias Humanas/metabolismo , Glândulas Mamárias Humanas/patologia , Pessoa de Meia-Idade , Estudos Prospectivos , Microambiente Tumoral
18.
Biochim Biophys Acta ; 1857(4): 443-53, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26768115

RESUMO

Cardiolipin (CL) is a unique mitochondrial phospholipid potentially affecting many aspects of mitochondrial function/processes, i.e. energy production through oxidative phosphorylation. Most data focusing on implication of CL content and mitochondrial bioenergetics were performed in yeast or in cellular models of Barth syndrome. Previous work reported that increase in CL content leads to decrease in liver mitochondrial ATP synthesis yield. Therefore the aim of this study was to determine the effects of moderate decrease in CL content on mitochondrial bioenergetics in human hepatocytes. For this purpose, we generated a cardiolipin synthase knockdown (shCLS) in HepaRG hepatoma cells showing bioenergetics features similar to primary human hepatocytes. shCLS cells exhibited a 55% reduction in CLS gene and a 40% decrease in protein expression resulting in a 45% lower content in CL compared to control (shCTL) cells. Oxygen consumption was significantly reduced in shCLS cells compared to shCTL regardless of substrate used and energy state analyzed. Mitochondrial low molecular weight supercomplex content was higher in shCLS cells (+60%) compared to shCTL. Significant fragmentation of the mitochondrial network was observed in shCLS cells compared to shCTL cells. Surprisingly, mitochondrial ATP synthesis was unchanged in shCLS compared to shCTL cells but exhibited a higher ATP:O ratio (+46%) in shCLS cells. Our results suggest that lowered respiratory chain activity induced by moderate reduction in CL content may be due to both destabilization of supercomplexes and mitochondrial network fragmentation. In addition, CL content may regulate mitochondrial ATP synthesis yield.


Assuntos
Trifosfato de Adenosina/biossíntese , Cardiolipinas/análise , Transporte de Elétrons , Hepatócitos/metabolismo , Células Cultivadas , Metabolismo Energético , Humanos , Mitocôndrias/metabolismo
19.
J Proteome Res ; 15(3): 868-78, 2016 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-26754345

RESUMO

The fatty acids composition of adipose tissue may provide information on the nutritional part of the risk or evolution of breast cancer. To determine whether (1)H NMR of adipose tissue provides information on the nature of the diet consumed, a dietary intervention with increasing percentage of polyunsaturated n-3 docosahexaenoic acid (DHA 22:6n-3, provided as DHASCO oil) was applied to a rat model of N-nitroso-N-methylurea-induced mammary tumors. Spectra of the lipid extracts were obtained from adipose tissues in five groups of Sprague-Dawley rats fed with a diet containing 7% peanut/rapeseed enriched with 8% (w/w) of an oil without (palm oil) or with low (1%), moderate (3%), or high (8%) DHASCO content. A control group received a basal diet with 15% peanut/rapeseed representative of the "Western" diet. After 5 months of those five controlled diets, adipose tissue was collected for analysis of the lipid extract using both (1)H NMR analysis on an 11.7 T spectrometer and gas chromatography considered as gold standard. (1)H NMR analysis showed a dose-dependent increase in DHA in the lipid extract of adipose tissues and a commensurate decrease in n-6 polyunsaturated fatty acids in the three DHA groups, which allowed one to follow n-6/n-3 ratio changes. The highest n-6/n-3 ratio was observed in the control Western diet group compared to the other diet groups. The integrated spectral regions showed separation between groups, thereby documenting a specific NMR lipid profile corresponding to each dietary intervention. Those diet-dependent NMR lipid profiles were consistent with that obtained with gas chromatography analyses of the same samples. This study is a proof of concept highlighting the potential use of the (1)H NMR approach to evaluate dietary intervention in biopsies of adipose tissues.


Assuntos
Tecido Adiposo/química , Gorduras na Dieta/administração & dosagem , Ácidos Docosa-Hexaenoicos/administração & dosagem , Espectroscopia de Ressonância Magnética , Neoplasias Mamárias Experimentais/metabolismo , Animais , Ácidos Docosa-Hexaenoicos/análise , Ácidos Graxos Ômega-3/administração & dosagem , Ácidos Graxos Ômega-3/análise , Ácidos Graxos Ômega-6/análise , Feminino , Lipídeos/química , Neoplasias Mamárias Experimentais/induzido quimicamente , Ratos , Ratos Sprague-Dawley
20.
Biochim Biophys Acta ; 1851(11): 1490-500, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26327596

RESUMO

Cardiolipin (CL) content accumulation leads to an increase in energy wasting in liver mitochondria in a rat model of cancer cachexia in which tumor necrosis factor alpha (TNFα) is highly expressed. In this study we investigated the mechanisms involved in liver mitochondria CL accumulation in cancer cachexia and examined if TNFα was involved in this process leading to mitochondrial bioenergetics alterations. We studied gene, protein expression and activity of the main enzymes involved in CL metabolism in liver mitochondria from a rat model of cancer cachexia and in HepaRG hepatocyte-like cells exposed to 20 ng/ml of TNFα for 12 h. Phosphatidylglycerolphosphate synthase (PGPS) gene expression was increased 2.3-fold (p<0.02) and cardiolipin synthase (CLS) activity decreased 44% (p<0.03) in cachectic rat livers compared to controls. CL remodeling enzymes monolysocardiolipin acyltransferase (MLCL AT-1) activity and tafazzin (TAZ) gene expression were increased 30% (p<0.01) and 50% (p<0.02), respectively, in cachectic rat livers compared to controls. Incubation of hepatocytes with TNFα increased CL content 15% (p<0.05), mitochondrial oxygen consumption 33% (p<0.05), PGPS gene expression 44% (p<0.05) and MLCL AT-1 activity 20% (p<0.05) compared to controls. These above findings strongly suggest that in cancer cachexia, TNFα induces a higher energy wasting in liver mitochondria by increasing CL content via upregulation of PGPS expression.


Assuntos
Caquexia/metabolismo , Cardiolipinas/metabolismo , Regulação Neoplásica da Expressão Gênica , Hepatócitos/metabolismo , Neoplasias Peritoneais/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Aciltransferases/genética , Aciltransferases/metabolismo , Animais , Caquexia/genética , Caquexia/patologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Metabolismo Energético/genética , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Mitocôndrias Hepáticas/patologia , Fosforilação Oxidativa/efeitos dos fármacos , Neoplasias Peritoneais/genética , Neoplasias Peritoneais/patologia , Ratos , Transdução de Sinais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transferases (Outros Grupos de Fosfato Substituídos)/genética , Transferases (Outros Grupos de Fosfato Substituídos)/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/farmacologia
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